91 Ford AC electrical


Asked by Aug 14, 2016 at 09:42 PM about the 1991 Ford F-350 2 Dr STD 4WD Standard Cab LB

Question type: Maintenance & Repair

I have a 91 F350 Custom with the 460. It didn't come from the factory with
AC, and now I'm trying to install AC into the truck. The system came out of
a 93 F150, So it is a factory system. I currently have two hot wires, that
when connected and low pressure bypassed  sends power to the
compressor. So I have two hots at the compressor. Is this right? I don't
have another truck to test the power and Google isn't helping.

2 Answers


You most likely have two powers but only one goes to the compressor clutch the other feeds in input to the ECM for the A/C on signal, but as you have a 91 truck, one wire will not be used. I have a wiring diagram but for some reason I can't get it to download to the site.


Try www.fordforums.com

Your Answer

Add photo

Related Questions

  • I need body ground Schematics for a 1995 f350 ford dump 8 answers

    I have a ground problem on my truck, and I have replaced some of them but I cannot find all of them so I would like to have some Schematics so I know where all my body grounds are.

    1995 Ford F-350


    Maintenance & Repair

  • Why does my diesel truck die when I'm driving? 16 answers

    I have a 1984 Ford F350 Diesel truck. Has 6.9 motor. Truck starts okay and will idle all day long. But as soon as I start to drive anywhere it acts like it's running out of fuel and dies. I made sur...

    1984 Ford F-350


    Maintenance & Repair

  • why is the break lights not working 3 answers

    when pushing down on pedal, the break lights dont work, but if i push the button on electric break box inside, they work

    1991 Ford F-350 2 Dr STD Extended Cab LB


    Maintenance & Repair

  • 1988 F350 Dual fuel tanks was working fine, now, i am getting interesting results 1 answer

    1988 F350 Diesel 2wd manual trans Dual tanks Has been working fine, gas gauge was nearing 1/4th tank so I switched from Rear to front (about 3/4 tank ) and pulled into gas station - only took 5 g...

    1988 Ford F-350


    Maintenance & Repair

  • how to open the liftgate when the battery is dead? 9 answers

    I want to open the liftgate manually to take the 120 v convenience cord out for charging, because no power in the battery. Please tell me how to open the liftgate? Thanks!

    2015 Ford Focus Electric


    Maintenance & Repair

Search Ford F-350 Questions

Ford F-350 Experts

#1 BoholMark
Reputation 110
#2 Alexander Curtis
Alexander Curtis
Reputation 60
#2 tennisshoes
Reputation 60
View All

Related Models For Sale

Used Ford F-250"
603 listings starting at $3,995
Used Ford F-150"
3,181 Great Deals out of 216,388 listings starting at $1,900

Used Cars For Sale